Fourth Port Research Articles

Mahogany: a historical geography of a lasting commodity of 18th-century enslavement

ABSTRACT It might be assumed that the commodities produced by enslaved labour in the British colonies in the 18th century were consumed long ago. Mahogany wood, however, endures and challenges this assumption. Slave labour was used to cut mahogany trees and prepare the timber for transporting to European and North American markets. When made into fine furniture and fittings this same mahogany has been admired and preserved through to the present day. We explore how mahogany was part of the geography of colonial trade and wealth-making by drawing on research focused on Lancaster in north-west England, the UK’s fourth largest slave trading port. We trace the extended geographies and lines of connection that were produced by the interlinked trades in enslaved African people and mahogany wood, and, through this focus on Lancaster, we provide an example of how colonialism shaped the economy and narrative of places in Britain. Contemporary responses within heritage settings and the implications for the continuing trade in antique mahogany furniture are also considered.

V04-06 ROBOTIC ASSISTED TRANS-VESICOSCOPIC URETERIC REIMPLANTATION IN CHILDREN: SURGICAL ERGONOMICS RELATED TO MUSCULOSKELETAL SYMPTOMS

You have accessJournal of UrologyCME1 Apr 2023V04-06 ROBOTIC ASSISTED TRANS-VESICOSCOPIC URETERIC REIMPLANTATION IN CHILDREN: SURGICAL ERGONOMICS RELATED TO MUSCULOSKELETAL SYMPTOMS MS Ansari, Prabhu Karunakaran, Sanjoy Sureka, and Priyank Yadav MS AnsariMS Ansari More articles by this author , Prabhu KarunakaranPrabhu Karunakaran More articles by this author , Sanjoy SurekaSanjoy Sureka More articles by this author , and Priyank YadavPriyank Yadav More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000003252.06AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Robot-assisted surgery has been reported to provide many benefits over open surgeries to the patient and surgeon. Many surgeons experience work-related pain and musculoskeletal symptoms. Neck strain, back strain/pain and lower extremity exertion have been reported up to 20-40% of the surgeons in open surgeries. We sought to evaluate the feasibly of robotic assisted trans-vesicoscopic ureteric reimplantation in children and surgeons' work-related musculoskeletal symptoms in comparison to open surgery METHODS: The children under 12 years of age with vesicoureteric reflux (VUR underwent open) (Group I) and vesicoscopic robotic assisted ureteric reimplantation (VRAUR) (Group II). All surgeries were performed by a single surgeon. For VRAUR the patient was placed in a dorsal lithotomy position. Four ports (Two 8-mm working ports were placed in a straight line drawn along the anterior superior iliac spine and one endoscopic [middle]) 12 mm (Intuitive Surgical, Sunnyvale, CA), was placed 2 cm above the same line and the fourth assistant port of 3 mm was placed 2 cm below the line. The surgeons related ergonomic parameters recorded in both the groups were generalised pain, neck and back strain/pain along with lower extremity exertion to surgeons (assessed as per visual analogue scale [VAS]). Success was defined as the absence of VUR on direct radionuclide cystogram at 12 weeks. RESULTS: The median age of the children was 4.5 and 5.1 in groups I and II respectively. Both the groups had 30 of patients each. The grades of VUR was comparable in both the groups. The VRAUR procedure could be accomplished in all the cases without any slippage of robotic ports or clashing of arms except in 2-year-old that without any conversion. The 2-yr-old child with bladder capacity of 150 cc posed little difficulty due to space restriction and slight clashing of arms that lengthened the procedure but could be completed successfully. The mean operative time was 95 (90-122) and 140 (115-160) minutes (p=0.029) in groups I and II respectively with a successes rate of 96.7 and 93.3 (p=0.031) respectively. The Surgeons’ musculoskeletal VAS scores recorded were substantially more in Group I as compared to Group II (p value 0.03, OR 3.9 [1.9-5.4]). CONCLUSION: Robotic assisted laparoscopic ureteral reimplantation is feasible and offers success rate comparable to open surgery. The surgical ergonomics related to musculoskeletal symptoms are more substantial in open surgery. Source of Funding: None © 2023 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 209Issue Supplement 4April 2023Page: e339 Advertisement Copyright & Permissions© 2023 by American Urological Association Education and Research, Inc.MetricsAuthor Information MS Ansari More articles by this author Prabhu Karunakaran More articles by this author Sanjoy Sureka More articles by this author Priyank Yadav More articles by this author Expand All Advertisement PDF downloadLoading ...

Laparoscopic Treatment of Perforated Appendicitis

The most frequent general surgical emergency worldwide is acute appendicitis. Because to its potentially fatal complications, including perforation, it could put patients at danger of death. An appendix that has ruptured frequently results in serious infectious complications as abdominal sepsis, pelvic abscess, and others. Laparoscopic appendectomy for perforated appendicitis raises several questions. In many nations today, laparoscopic treatment of perforated appendicitis is the preferred surgical technique. Aim: This prospective study's objective was to assess the efficacy of laparoscopy in the treatment of complicated appendicitis (perforation). Methods: The study was conducted prospectively during the period from September 2020 to August 2022. The study included 50 individuals who underwent peritoneal lavage after laparoscopic appendicectomy of perforated appendix in the department of Surgery, Lady Reading Hospital, Peshawar. The traditional method, three ports technique was used. Sometimes a fourth port is needed. Telescopic ports are 10 mm in size. The other two ports are 3/5 mm and 5/10 mm, respectively. Unipolar diathermy is a source of energy. Hemostasis and ligation of the appendicular stump are achieved via intra-corporeal knotting, endo-loop, and hemo-clip. Results: The study's age range is 5-70 years, with a mean age of 19 with male predominance. The duration of surgery varies from 30 to 120 minutes, with a mean duration of 65 minutes. Hospital stays range from 48 to 96 hours on average. There were 12 patients with complications, including paralytic ileus was seen in 1(2%), diarrhea in 2(4%), multiple or single (4% and 8%) port infections, and port TB in (4%). Open conversion was seen in 1 (2%) patient due to appendicitis burst haemorrhage. Every complication was treated carefully. Conclusion: Laparoscopy is an excellent method for treating perforated appendicitis. Thus, it is practical, achievable and may be carried out by skilled hands in any centre. That is now regarded as regular operating procedure. Keywords: Laparoscopic appendicectomy, Perforation (burst)

Predictive load accommodation in a micro-grid

This manuscript applies model prediction-based control (MPC) to accommodate the variable ac-natured load (AL) by optimally allocating the fuel cell (FC), battery, solar photovoltaic (SP) power in a four-port dc/dc converter (FPDDC). The presented work considers the FC, battery, SP, and AL at the first, second, third, and fourth ports of the FPDDC, respectively. The small signaled state-space representation of the FPDDC has been obtained through the improved cyclic averaged current. Then, to get the receding horizon-based MPC optimal control action, ∆u * [k] ; k = 0, 1, 2, 3, . . ., the above-mentioned model of the FPDDC is discretized. The ∆u * [k] has been obtained by formulating a performance index, Ja [k] based on an error minimization between the reference AL power demand, rpd [k] and the actual AL power, y [k]. The corresponding results have been obtained through the Simulink platform of the MATLAB. Further, the article takes sequential quadratic programming (SQP) into consideration to benchmark these solutions.

Switchable edge-line coupler based on parity time-reversal duality symmetry

A compact broadband Edge-Line Coupler (ELC) based on Parity Time-reversal Duality (PTD) symmetry has been conceived, designed, constructed and measured. The coupler connects four PTD bifilar edge lines (BELs), recently introduced by the authors. The PTD-BELs are constituted by a parallel plate waveguide whose walls are formed by a junction between Perfect Electric Conductor (PEC) and Perfect Magnetic Conductor (PMC) boundary conditions. Reversing the axis orthogonal to the plates interchanges the position of PEC and PMC. Such a waveguide supports unimodal transverse electromagnetic (TEM) propagation, extremely confined along the top and bottom junction edges; its propagation is protected against backscattering from any discontinuity that preserves the PTD symmetry. The ELC presented here is constituted by a 4-port junction in which each port is intrinsically matched due to the PTD symmetry, strongly coupled with a second port, strongly decoupled with a third port, and weakly coupled with a fourth port. The ELC is designed by using a mushroom metasurface for the PMC portion of the device; the connection is based on a switch circuit which imposes open and short conditions on the two opposite sides of the structure. Switching simultaneously the open and short circuits reroutes the signal in a different port, while maintaining the same level of coupling with the other ports. A static prototype has been built and its measurements have confirmed the matching performance and the good directionality of the coupler in a broadband frequency range between 24 and 30 GHz.

OC-030 EARLY OUTCOMES OF ROBOTIC TAPP HERNIA REPAIR FOR INGUINAL HERNIA: A SINGLE SURGEON'S EXPERIENCE

Abstract Aim The aim of this study was to evaluate the early outcomes of robotic TAPP (trans abdominal pre-peritoneal) inguinal hernia repair in a tertiary hospital. Material & methods This is a retrospective analysis of patients who underwent robotic TAPP by a single surgeon from November 2019 to May 2022. Three-arm, 4-port technique of robotic TAPP was performed. The patient cart was advanced depending upon laterality of the hernia. Three ports were placed in a linear fashion at the level of umbilicus, and the fourth port or assistant port was taken on the side opposite to the cart, triangulated from the umbilical and lateral ports. Results 37 male patients were included, of which, 16 had unilateral hernias and 11 had bilateral hernias. Mean age was 46.2 (SD 16.5) years. One patient had a recurrent groin hernia after open repair. Mean operating time was 137.6 (SD 33.2) minutes. Operating time for the first ten cases was 158.2 (SD 25.1) min, and that of the last ten cases was 127 (SD 42.2) minutes, showing a steady decrease over time. One patient had intraoperative injury of the vas deferens, which was repaired. Mean hospital stay was 1.4 (SD 0.8) days. One patient had seroma. None of the patients had recurrence or mesh infection. Conclusions Robotic TAPP is a safe and effective procedure for the repair of inguinal hernias. Placing of assistant port near the umbilicus offers ergonomic advantage over linear port placement.

Holistic environmental monitoring in ports as an opportunity to advance sustainable development, marine science, and social inclusiveness

Ports play a central role in our society, but they entail potential environmental risks and stressors that may cause detrimental impacts to both neighboring natural ecosystems and human health. Port managers face multiple challenges to mitigate risks and avoid ecosystem impacts and should recognize that ports are embedded in the wider regional coastal ecosystem. Cumulative impacts of anthropogenic stressors have the potential to further burden the existing suite of natural stressors, particularly where ports are located in embayments and estuaries. Environmental monitoring in ports should thus develop a comprehensive, holistic, multilayered approach integrated in the wider ecosystem that will help managers better achieve sustainable development, a major goal of the United Nations’ 2030 agenda and Decade of Ocean Science for Sustainable Development (2021–2030). This practice bridge showcases the experience of the second Canadian Healthy Ocean Network (CHONe2) in Baie des Sept Îles (BSI, Quebec; the fourth largest industrial port in Canada) laying the foundations of holistic environmental monitoring in ports. We describe the partnership model (i.e., engaging scientists, local authorities, an independent organization, and local industries), synthesize the multidisciplinary studies that turned environmental monitoring into a systemic investigation of the biological and physical components of BSI, integrate the developed scientific knowledge into a social–ecological–environmental system, present an innovative near real-time monitoring approach, and discuss implications for management and policy. The CHONe2 experience in BSI aligns with the decade’s road map for sustainable development and provides elements that could be adapted to other commercial ports. By suggesting a set of best practices (e.g., multidisciplinarity, transparency, inclusivity, participatory modeling), we hope to spark new interest in environmental monitoring as a path to conciliate development and sustainability of ports and other high-use marine areas.

Feasibility and Safety of Three-Port Laparoscopic Cholecystectomy Compared to Four-Port Laparoscopic Cholecystectomy.

BackgroundThe standard four-port laparoscopic cholecystectomy (LC) is the gold standard procedure. The various clinical trials and reports in the literature have suggested that the three-port technique LC can be done safely with acceptable results.Still, that the three-port LC offers any added benefits to the patient is a controversial issue especially in view of safety and feasibility. In this study, we report the experience of three-port LC compared to four-port LC technique, its safety, feasibility and outcomes.Materials and methodsA prospective randomized study was conducted between two groups which included 165 cases - 93 patients were included in three-port LC (Group A) and 72 patients in four-port LC (Group B). Operative time, intraoperative complications, postoperative pain, length of hospital stay, analgesics requirement, conversion to open and return to normal activities were parameters of evaluation.ResultsDemographic data was comparable in both the groups. Three-port LC Group A had lesser post-operative pain and analgesics requirements. The mean postoperative pain visual analogue scale (VAS) score on day 1 was (4.16 and 6.24), on day 7 was (1.26 and 1.81) in three-port group and in four-port LC group, respectively. The mean days of analgesics requirement were 2.56 days and 4.21 days among three-port group and four-port group, respectivelyLength of hospital stay was less and returning to work was early in three-port group. There was no statistical difference in operative time. The mean operative time among three-port LC group A and four-port LC group B was 36+/-8.6 minutes (30-68) and 39+/-7 minutes (30-90), respectively. The overall outcomes were comparable to four-port LC.ConclusionThree-port LC is a feasible and safe procedure for LC with satisfactory outcomes like lesser postoperative pain, postoperative stay and less scars, when performed by experienced hands, especially in acute cholecystitis. The use of fourth port should be done when required in a difficult situation.

Robotic Ureteral Reimplantation: Nonrefluxing Intravesical and Extravesical Techniques

Introduction: Nonrefluxing ureteral reimplantation is the gold standard surgical management of patients with symptomatic vesicoureteral reflux (VUR).1,2 Intravesical and extravesical ureteral reimplantation were traditionally performed with an open approach through the Cohen, Lich-Gregoir, Glen-Anderson, and Politano-Leadbetter techniques.3 However, there has been recent adoption of minimally invasive approaches including the use of robotic assistance.1 Moreover, these nonrefluxing ureteral reimplantation techniques have been primarily described in the pediatric population rather than in adults.2 We demonstrate our techniques and describe outcomes of adult patients undergoing nonrefluxing intravesical and extravesical robotic ureteral reimplantation (RUR). Materials and Methods: We reviewed our institution's own robotic ureteral reconstruction database to identify consecutive adult patients with a history of VUR who underwent nonrefluxing intravesical or extravesical RUR between September 2016 and November 2020. Indications for surgery included patients with symptoms of flank pain and/or recurrent infections secondary to VUR. Our primary outcome was surgical success, which we defined as the absence of postoperative flank pain and radiographic absence of VUR on voiding cystourethrogram or obstruction on diuretic renal scan. Before beginning the procedure, all patients underwent cystoscopy, cystogram, and/or retrograde pyelogram. Robotic ports are placed similarly for both techniques through the standard prostatectomy configuration without a fourth robotic port or the right lateral 12 mm assistant port. A 5 or 12 mm assistant port is placed between the camera and the right robotic port. Meticulous dissection of the distal ureter to preserve its fragile blood supply is performed for both techniques. In the robotic intravesical technique, adapted from the Politano-Leadbetter technique, the ureter is redirected through a new supratrigonal hiatus and submucosal tunnel created in a 5:1 ratio.4 The neoureteral orifice (UO) is relocated distally (subtrigonometry) and medial to the orthotopic UO. In the robotic extravesical technique, adapted from the Lich-Gregoir technique, a mucosa sparing extravesical tunnel is created according to the Paquin guidelines with a 5:1 length to diameter ratio.5,6 In patients who have a previous ureteroneocystostomy complicated by reflux symptoms, the existing reimplant site can be left intact and revised with an extravesical tunnel to prevent reflux. Results: Three patients met inclusion criteria. Two patients underwent nonrefluxing extravesical RUR and one patient underwent intravesical RUR. The patient who underwent an extravesical RUR had a history of reimplantation that was complicated by severe reflux-related symptoms. Intraoperatively, the mean estimated blood loss was 50 mL and mean robotic console time was 162 minutes. Postoperatively, none of the patients experienced major (Clavien >2) complications. With regard to surgical success, at a mean follow-up of 20.5 months, all patients were free of urinary tract infections and obstructive flank pain symptoms. In addition, all patients achieved complete resolution of VUR on postoperative voiding cystourethrogram or renal scan. Conclusions: Nonrefluxing intravesical and extravesical RUR may be safely and effectively utilized for surgical management of adult patients with symptomatic VUR. Moreover, the nonrefluxing extravesical RUR can be used to revise select patients with prior reimplantation complicated by symptomatic reflux. S.K., C.O., and M.L. have no competing financial interests. D.D.E. reports a relationship with Intuitive Surgical that includes consulting or advisory and speaking and lecture fees. D.D.E. reports a relationship with Melzi Corp that includes board membership. D.D.E. reports a relationship with Johnson and Johnson that includes consulting or advisory. Accepted for presentation at Mid-Atlantic AUA 2021. Patient Consent Statement: Authors have received and archived patient consent for video recording/publication in advance of video recording of procedure. Music: Music (Gentle Wave by Ketsa) is not copyrighted material and was obtained from a royalty-free source. Runtime of video: 7 mins 14 secs

A tuneable rat-race coupler for full duplex communications

AbstractFull duplex (FD) could potentially double wireless communications capacity by allowing simultaneous transmission and reception on the same frequency channel. A single antenna architecture is proposed here based on a modified rat-race coupler to couple the transmit and receive paths to the antenna while providing a degree of isolation. To allow the self-interference cancellation (SiC) to be maximized, the rat-race coupler was made tuneable. This compensated for both the limited isolation of the rat race and self-interference caused by antenna mismatch. Tuneable operation was achieved by removing the fourth port of the rat race and inserting a variable attenuator and variable phase shifter into the loop. In simulation with a 50 Ω load on the antenna port, better than −65 dB narrowband SiC was achieved over the whole 2.45 GHz industrial, scientific and medical (ISM) band. Inserting the S-parameters of a commercially available sleeve dipole antenna into the simulation, better than −57 dB narrowband SiC could be tuned over the whole band. Practically, better than −58 dB narrowband tuneable SiC was achieved with a practical antenna. When excited with a 20 MHz Wi-Fi signal, −42 dB average SiC could be achieved with the antenna.

Fewer Ports Cut Opioid Use and Length of Stay in Elective Laparoscopic Cholecystectomy

Background:Postoperative pain is one of the most common reasons for prolonged hospital stay with opioid analgesia the mainstay of treatment.Objectives:The purpose of this study was to determine whether the degree of abdominal trauma, reflected by the number and sizes of ports used in elective laparoscopic cholecystectomy, correlated against opioid analgesia requirements and length of stay.Methods:A retrospective clinical audit was undertaken of 144 patients who underwent elective laparoscopic cholecystectomies with 3-port (12/5/5) and 4-port approaches (12/5/5/5 and 12/10/5/5). In the reduced port cases, liver retraction was achieved using a suction retractor, removing the requirement for a fourth port. The number of ports and total cross-sectional area of all ports were compared against the procedure time, length of stay, and opioid analgesia required.Results:The smaller total cross-sectional area associated with the 3-port approach (12/5/5, 277.25 mm2) resulted in significantly lower total oral morphine equivalent daily dose required compared to 12/10/5/5 (453.96 mm2) and 12/5/5/5 (327.52 mm2) approaches, being 30.7 mg and 21.0 mg less, respectively (p < 0.001). The 3-port approach had a mean length of stay 0.8 days which was significantly shorter compared to both 4-port approaches (p = 0.001, length of stay of 1.1 and 1.2 days for 12/5/5/5 and 12/10/5/5, respectively). Laparoscopic cholecystectomy patients in the study hospitals routinely stayed overnight.Conclusions:The absolute number of ports used in elective laparoscopic cholecystectomies appears to play an important role in postoperative recovery. In particular, 3-port configurations may result in less postoperative pain without the burden of an increase in length of stay, morbidity, or mortality rates.

РАСЧЕТ РЕЙСОВОГО ГРУЗОВОГО ПЛАНА КОНТЕЙНЕРОВОЗА

The questions of drafting of cargo plan of containership on a voyage are considered in work, duting of which the reception and unloading of parties of containers is produced in a few ports. Forming of loading of the ship «Sky Gemini », which can adopt containers in eight holds and on their lids is considered. Placing of containers can be produced in 16 cargo apartments, thus in each of cargo apartment it is possible to place 192 twenty foot container. The voyage of ship with arrival in five ports is considered in the article, thus in the first port the complete loading of ship is produced 3072 containers, gross weight of which makes 45000 т. A load consists of three parties which are addressed accordingly in fifth, fourth and second ports. In the second port the second party and ship unloads with two remaining parties follows in the third port, where fourth party of containers for fourth port is loaded. Unloading of the third and fourth parties is produced in fourth port, and a ship with the unique first party accomplishes transition in the last fifth port. As a result of every loading of parties of containers list of ship must be in limits from 0 to -2,0 м. List, which placing of containers, suiting longitudinal durability, corresponds to, gets out from the indicated interval. Therefore, for every party of loading it is necessary to find the scope values of static moments which provide list of ship accordingly 0 and -2,0 м. The results of imitation design of four loads of ship are represented. As the conducted imitation design showed, the computer program formed the loads of ship, the feature of which there is their admission on the requirements of his landing, stability and general longitudinal durability. Minimization of forces of inertia at tossing of ship during transition is attained by the order of piling of containers in every tier: containers with greater mass are disposed nearer to the diametric plane of ship. In the imitation program is present module of estimation of parameters of landing, stability and longitudinal durability of the ship «Sky Gemini», using his hydrostatical tables and information about durability. Taking into account distributing of weight of containers of parties of loading, the criteria of nautical safety of ship, which are represented as the diagram of static stability, shire forces and bending moments, settle accounts by the program.

The New Concept of Fifth Generation Port And Navigation Engineering

This paper puts forward the concept of port and navigation engineering of the fifth generation. Starting from the concept of port, it points out that port has gone through the change from the first generation port to the fourth generation port, and now it has entered the stage of the fifth generation port. The main functions of the fifth generation port include the functions of the previous four generations, while it also focuses on the combination of port city and port town, and its main characteristics are efficiency, ecology and low carbon. Then it puts forward the concept of ecological port and navigation in narrow sense and broad sense. In the narrow sense, the ecological port and navigation refers to the ecological port of the fifth generation port above the third and fourth generation ports and the ecological channel centered on the ecological port. In the broad sense, ecological port and navigation refers to the port and navigation system that combines ecological port, ecological channel, ecological port city and ecological village. The fifth generation port and navigation engineering is the port and navigation engineering corresponding to the fifth generation port, ecology is its most important feature, which is the new promotion of port and navigation engineering concept.

Robotic esophagectomy with total mediastinal lymphadenectomy using four robotic arms alone in esophageal and esophagogastric cancer (RETML-4): a prospective feasibility study.

Robotic-assisted esophagectomy is still in the implementation phase. Robotic surgical systems refine visualization via robotically-enhanced surgical anatomy (RESA), and the stable articulated robotic arms provide precise movements. This prospective feasibility study was conducted to evaluate robotic esophagectomy with total mediastinal lymphadenectomy using four robotic arms exclusively (RETML-4). The inclusion criterion was clinical stage I-IIIB esophageal cancer with stable general condition. Patients were positioned hemi-prone with single-lung ventilation, and the operation table was tilted until the patient was prone. The first, second, third, and fourth robotic ports were inserted into the ninth intercostal space (ICS) on the angulus inferior scapulae line, seventh ICS on the posterior axillary line, and the fifth and third ICS on the mid-axillary line, respectively. RETML-4 was performed by precise sharp dissection in wide stable operation fields, with countertraction created by a tip-up fenestrated grasper with gauze. Esophagectomy was performed separately for the middle to lower, and upper esophagus. After mobilizing the middle to lower esophagus and performing lymph node dissection, the upper esophagus was mobilized, with bilateral lymph node dissection along the recurrent laryngeal nerves. The assistant surgeon was involved only during removing gauze and collecting harvested lymph nodes in the thorax. RETML-4 was performed in all ten patients enrolled in 2018. The median postoperative hospital stay was 15days, and the complication rate was 60%. Nine cases achieved R0 resection. Recurrence occurred in two cases. RETML-4 is feasible, and may facilitate minimally invasive esophagectomy by providing precise instrument movements and RESA.

Opioid free anesthesia in patients undergoing three-ports laparoscopic cholecystectomy

Abstract Background: After considerable experience with laparoscopic cholecystectomy (LC) using four ports, Authors began the three‐port LC. Opioid free anesthesia OFA means a technique in which no intraoperative opioid is administered through any route. Objectives: Study aims to assess both of the safety while using 3 ports during the laparoscopic cholecystectomy procedures and the efficiency of the Opioid Free Anesthesia throughout the perioperative period. Patients and Methods: Patients were scheduled for elective laparoscopic cholecystectomy and classified randomly into two groups, each one contained 25 patients. Group one has submitted for Opioid Based Anesthesia protocol and group two has submitted to Opioid Free Anesthesia protocol. Surgical technique was Laparoscopic cholecystectomy and it was first tried by 3 port then the fourth port is inserted when indicated. Results: Three‐port LC successfully performed in 92% of cases of the study with safety. There were a statistically significant decrease in perioperative HR, and MAP. Study showed decrease in VAS score, post-operative Pethidine consumption and PONV. No major postoperative complications, as bile leakage or bleeding have been reported. Conclusion: Three‐port LC is a safe and technically feasible. Also OFA is superior to (OA) in anesthesia of patients undergoing LC.

Dynamically controllable graphene terahertz splitters with nonreciprocal properties.

Two novel graphene-based nonreciprocal four-port splitters for the terahertz region are proposed. The input power is divided between two output ports, whereas the input port is isolated from the output ports due to the presence of the fourth port. The splitters consist of a circular graphene resonator and four graphene waveguides coupled to the resonator. These elements are placed on the two-layer dielectric substrate. The central part of the splitter is under a biasing DC magnetic field normal to the graphene layer. The surface plasmon-polariton wave in the input port excites the dipole resonance in the resonator. The splitters have the following parameters: the input power is divided between two output ports almost equally with -4.4 dB. The input port is isolated from two output ports by -15 dB. The bandwidth is 4.0% with a central frequency of 7.4THz. The biasing DC magnetic field is 0.8T, and the Fermi energy of graphene ϵF=0.15 eV. Changing the Fermi energy by electrostatic gating allows one to dynamically control the central frequency of the splitters.

DESIGN, SIMULATION AND REALIZATION OF A COMPACT DUAL BAND MEANDERED COUPLER

Telecommunication systems increasingly require the use of miniaturized passive microwave components. One of these is the directional coupler, a four-port component intended to distribute power to two output ports, the fourth port being isolated. This paper proposes a dual-band branch-line coupler (BLC) with an extremely compact microstrip structure. The application of meandering lines as the coupler’s central connector yields dual-band operation. HFSS is used to optimize the device and to verify its transmission characteristics. This yields a design of a coupler with a footprint is 23×34.6 mm², operating at 1.65 / 3.30 GHz, with ports that can be adapted to a load impedance of 50 Ohm. To validate the model, the coupler is fabricated using microstrip technology on a FR4 substrate. A good agreement between measurement and simulation results is obtained. The coupler achieves an excellent isolation of –42.41 dB and a transmission loss of only –2.29 dB at 3.30 GHz.

Safety and feasibility of three port procedure in laparoscopic cholecystectomy

Background: Laparoscopic cholecystectomy is widely accepted gold standard technique for management of cholelithiasis and has undergone many refinements including decrease in size and number of ports. Many researchers have claimed that three-port laparoscopic cholecystectomy is safe and feasible method for management of cholelithiasis but still it is not performed widely by the surgeons. Objective of our study was to assess the safety and feasibility of three-port laparoscopic cholecystectomy by comparing the various defined parameters with the standard four-port laparoscopic cholecystectomy.Methods: The study included 100 patients and was divided equally in 2 groups. Patients in Group A underwent laparoscopic cholecystectomy by three-port technique and in Group B were operated by four-port technique. Patients in both the groups were compared in terms of operative time, intra-operative complications, post-operative pain, post-operative complications and cosmesis outcome.Results: The mean operative time was similar in both groups. Intra-op and post-op complications were also similar. 3 patients in Group A needed fourth port and 1 patient in both group required conversion to open cholecystectomy. Mean pain score and requirement of parentral analgesia was found to be lower in Group A. Duration of hospital was similar in both the groups. Patients in group A had slightly better cosmetic outcome.Conclusions: Three-port laparoscopic cholecystectomy is a minimally invasive, safe and feasible technique and is not difficult to master than other advanced techniques. In experienced hands, laparoscopy cholecystectomy can be initially started with three-ports and can be converted to four-port if rarely necessary.

China’s ‘One Belt, One Road’ Plan and Romania

China’s ‘One Belt, One Road’ Plan and Romania

Developing the fifth generation port concept model: an empirical test

PurposeThe purpose of this paper is to test the 5GP concept with measurement of the performance of Busan, Hong Kong, Singapore and Shanghai ports, employing a hybrid method of consistent fuzzy preference relation (CFPR), VIsekriterijumska Optimizacija i KOmpromisno Resenje (VIKOR) and PROMETHEE.Design/methodology/approachThe authors developed the concept of the fifth generation ports (5GPs), and apply CFPR, VIKOR and preference ranking organization method for enrichment evaluations (PROMETHEE) to evaluate the 5GPs.FindingsThe performance of the ports of Hong Kong and Singapore is close to meet the definition of 5GP criteria. On the contrary, ports of Busan and Shanghai are still behind the 5GP stage in light of the majority of the evaluation criteria’s performance.Research limitations/implicationsThis paper studies four ports. More empirical tests are needed to verify the applicability of the 5GP concept toward other ports.Practical implicationsThe findings provided port managers with the insight of how to improve their port to meet the criteria of 5GP.Social implicationsNew criteria and higher expectations of existing requirements present challenges to port managers for a need to raise the bar of service standards and develop new competencies.Originality/valueThe authors developed the concept of the 5GPs. Newly developed 5GP contributes to expanding the concepts of first to fourth generation ports developed by UNCTAD.